Matthew Barrows, of the Sacramento Bee, reports San Francisco 49ers OT Marvel Smith's (back) bad lower back has not improved over the offseason, and there is a good chance he will retire Sunday, Aug. 30, or Monday, Aug. 31, according to a source with knowledge of the situation.

Matthew Barrows, of the Sacramento Bee, reports San Francisco 49ers OT Marvel Smith (back) still has not been cleared to participate in every practice because of a lingering back problem. Smith does not want to return too early from the injury like he has in the past.